Fungus can hitchhike on used equipment from infected states.
Peanut producers advised to wash harvesting equipment before bringing to Arkansas.
Once established, fungus cannot be eradicated.
Fungus is has not been reported in Arkansas.

The University of Arkansas Division of Agriculture | Mar 19, 2012

Tiny fungal capsules hitchhiking on harvesting equipment from other states could bring an aggressive disease to Arkansas as farmers expand peanut acreage in the state.

“New peanut producers in the state are traveling out of state, mainly to Texas and Oklahoma, to buy used harvesting equipment for the upcoming season,” said Travis Faske, Extension plant pathologist for the University of Arkansas Division of Agriculture. “An aggressive disease of peanut and certain other crops, called Sclerotinia blight, could be hitching a ride to Arkansas on that equipment.”

Sclerotinia blight, caused by the soil-borne fungus Sclerotinia minor, is a significant peanut disease in Texas and Oklahoma, but hasn’t been reported in Arkansas. And once the fungus is in a field, it cannot be eradicated.

“Yield losses of 10 percent are common from this disease,” Faske said.

This fungus produces small black seed-like structures called sclerotia that are between 0.5 to 3 millimeters in size and can easily be carried in soil and peanut debris stuck to equipment.

“Sclerotia allow the fungus to survive for years, dormant in the soil plow layer,” said Terry Kirkpatrick, Extension nematologist. “When conditions are favorable, the fungus ‘germinates’ and infects a peanut host plant.

“The best way to control this disease in Arkansas is simply never to allow it to get established. Producers who buy equipment out of state should wash equipment thoroughly to remove any soil or plant material prior to bringing it onto their farm.

“This simple precaution could avoid a major problem for peanuts in Arkansas.”

Arkansas’ harvested acreage grew from about 2,000 in 2010 to 3,000 acres in 2011.